PROGRESSIVE EFFECTS OF MALACHITE GREEN AT VARYING CONCENTRATIONS ON THE DEVELOPMENT OF N-NITROSODIETHYLAMINE INDUCED HEPATIC PRENEOPLASTIC LESIONS IN RATS

Aims and background: Malachite green (MG) is a triarylmethane textile dye which is banned for use as a food colour, However, despite the ban it is used unscrupulously as a food colouring agent, It is also used extensively for dyeing silk, wool, lute, leather, cotton and also as a laboratory reagent, In view of its multipurpose utility, MG may pose a potential environmental health hazard. The purpose of this study was to evaluate the dose-dependent effects of malachite green on the deve lopment of pre-neoplastic lesions during N-nitrosodiethylamine (DEN)-i nduced hepato carcinogen es is in comparison with phenobarbitone (PB) in male Wistar strain rats, Methods: Rats were administered 200 p.p.m. DEN in drinking water for a period of one month, Following an interva l of two weeks the animals were given MG at concentrations of 25, 50 a nd 100 p.p.m. through drinking water for 7 months. PB at a concentrati on of 500 p.p.m. served as the standard tumour promoter, The dose depe ndent tumour enhancing effects of MG were monitored on the basis of mo rphological appearance of the livers, liver weight profile, histologic al pattern and quantitative GGT activity. Results: MG tested at all th e three concentrations and PB were found to enhance liver carcinogenes is to a significant extent when compared to either with their correspo nding controls or only the DEN treated animals, Conclusions: A dose-de pendent tumour enhancing effect of MG on DEN-induced hepatic preneopla sia in rats was observed, The enhancing effects at 25, 50 and 100 p.p. m. were found to be comparable with PB at 500 p.p.m.